The present invention relates generally to the art of lopping and pruning tools, particularly of the type including a pole or tubular tool support for reaching high branches and the like. More particularly, the invention relates to an improved telescoping lopper having an actuating arrangement that may be grasped in one hand for trimming relatively small branches, or in two hands where additional force is required for cutting larger branches. The invention also relates to a method for lopping including two movements of an actuator, a first engaging an actuating line and a second tensioning the line to move a blade to perform a desired cutting operation.
A great number and variety of devices have been proposed and are commercially available for lopping or pruning branches, limbs and the like. One type of lopping device, particularly suited to trimming high branches, includes a elongated shaft or tube on the upper end of which a lopping mechanism is mounted. The lopping mechanism includes a hook-shaped jaw and a pivotal blade. The blade is typically biased in an open position by a spring, and includes a lever arm extension attached to a cord or rope. To sever a tree branch or other object, a user places the jaw about the object and pulls the actuating cord to pivot the blade toward the jaw. A lopper generally of this type is described in U.S. Pat. No. 5,241,752, issued on Sep. 7, 1993 to Lutzke et al. and assigned to Fiskars Oy Ab.
Certain known lopping tools of this type have a shaft comprised of telescoping poles or tubes lockable with respect to one another in extended positions, greatly extending the reach of the device and allowing the user to trim high branches. A device of this type is described in U.S. Pat. No. 2,259,642, issued on Nov. 6, 1941 to Hoyt. In addition, such tools often include implements other than the jaw and blade structure, such as a saw, thereby adding to the utility and versatility of the device (see, e.g. U.S. Pat. No. 5,241,752 mentioned above).
Despite these improvements, known pruning and lopping tools can be difficult to use in many situations. One inconvenience associated with known lopping tools is that they require the user to hold and stabilize the shaft supporting the lopping head in one hand, while pulling the cord or cable to actuate the lopping tool with the other hand. With this type of lopper, when the user desires to cut tough or large diameter tree limbs and branches, the user may not be able to pull downwardly on the cord with sufficient force to sever the limb. Improvements in such devices have been proposed, such as that disclosed in U.S. Pat. No. 2,259,642, to facilitate holding the actuating cord, but nevertheless require the user to grasp the cord and hold it throughout the cutting operation.
Another inconvenience of many known lopping tools is a tendency for the actuating cords to become entangled. In most known lopping tools an actuating cord simply dangles from the lopping head and must be manually secured by the user prior to and throughout the cut. The cord typically hangs along side of the tool shaft where it can easily become entangled in branches and twigs surrounding the tool during use. In addition, for tools supported on telescoping tubes or shafts, excess cord typically dangles or is trailed below the shaft when the tool is collapsed (i.e. when the tubes are telescopingly retracted), such as for a low pruning task or for storing the tool, again making the cord susceptible to entanglement.
Lopping and pruning devices have been proposed that avoid the entanglement and cord tensioning problems mentioned above by passing one or more actuating cords or cables through the interior of a hollow telescoping shaft. In one device of this type, described in U.S. Pat. No. 5,084,975, issued on Feb. 4, 1992 to Melter and assigned to Fiskars Oy Ab, a pair of internal cables are coupled between an actuator and a shears. A compensating pulley permits extension of the telescoping tubes, while ensuring sufficient tension on the cord when a user desires to make a cut. However, the particular actuating arrangement of the tool generally does not permit a user to apply a maximum of actuating force to complete a difficult cut.
There is a need, therefore, for an improved lopping tool that avoids the inconveniences of currently available devices. In particular, there is a need for an extensible lopping tool that permits a user to exert force for completing a cut with both hands when necessary. There is also a need for an extensible lopping tool equipped with a system to collect and store excess actuating cord or cable, such as when the tool support is collapsed or stored, and to readily draw upon the stored cord or cable when needed to extend the support handle. In both cases, the improved tool should be of relatively simple, thereby permitting cost effective manufacture and improving, or at least maintaining, the useful life of the tool.
The present invention provides an innovative tool for lopping, trimming and pruning designed to respond to the needs identified in the foregoing. The tool features an extensible support tube through which an actuating cord or cable passes. The cable is associated with a clutch mechanism that permits unimpeded movement of the cable as the support tube is extended and retracted, but that engages the cable to actuate the lopper when a user displaces an actuating handle with respect to the support tube. The cable is conveniently collected and stored by a reel mechanism housed in the actuating handle. The actuating handle is moved through a first distance to engage the cable, then through a second distance to actuate the lopper. Because the actuating handle both causes actuation of the clutch mechanism and draws the cable to perform the cutting operation, a user may actuate the tool with one hand for less difficult cuts or apply a greater force on the handle with both hands when necessary. The clutch is automatically released and the cable collected after each cut.
Thus, in accordance with a first aspect of the invention, a tool for performing lopping, trimming, pruning and similar cutting operations includes an elongated tool support, a tool head, an actuating line and an actuating handle. The tool support has a central cavity extending at least partially through it and the tool head, including a cutting blade, is supported on its upper end. The actuating line is coupled to the tool head and is tensionable to move the cutting blade. The actuating line passes through at least a portion of the central cavity of the tool support. The actuating handle is coupled to the lower end of the tool support and includes an actuating line engagement mechanism. The engagement mechanism engages the actuating cable by a first movement of the actuating handle and tensions the actuating cable to move the cutting blade by a second movement of the actuating handle.
In accordance with another aspect of the invention, a tool includes an elongated, telescoping, extensible and retractable tool support having a central cavity extending at least partially therethrough. A severing tool is supported on the upper end of the tool support and includes a blade movable to perform a cutting operation. An actuating line is coupled to the severing tool and is tensionable to move the blade to perform the cutting operation. The actuating line extends through at least a portion of the central cavity of the tool support toward the lower end of the tool support. An actuating mechanism is provided for selectively engaging and tensioning the actuating line. A reel mechanism is disposed adjacent to the lower end of the tool support and is coupled to the actuating line. The reel mechanism collects the actuating line upon retraction of the tool support and dispenses the actuating line upon extension of the tool support.
In accordance with a further aspect of the invention, a tool includes an elongated tool support, a tool head, an actuating line and an actuating handle. The actuating handle is coupled to the lower end of the tool support and to the actuating line, the line passing at least through a portion of a central cavity in the tool support. The actuating handle is slidable with respect to the tool support in a first direction to tension the actuating line and move the blade to perform a cutting operation. The actuating handle can be slid in a second direction to relax the actuating line.
In accordance with still another aspect of the invention, a convenient method is provided for actuating a cutting tool of the type having an elongated tool support, a tool head secured to an upper end of the tool support and including a movable blade, an actuating line coupled to the tool head and tensionable to move the blade, and an actuating member mounted on a lower end of the tool support and coupled to the actuating line to selectively move the blade. The method includes a first step of moving the actuating member through a first distance in a predetermined direction with respect to the tool support to engage the actuating line. With the actuating line thus engaged, the method includes a second step of moving the actuating member through a second distance in the predetermined direction to tension the actuating line and thereby to perform the desired cutting operation.